Content: This study examines the progress made by two new reanalyses in the estimation of surface irradiance: ERA5, the new global reanalysis from the ECMWF, and COSMO-REA6, the regional reanalysis from the DWD for Europe. Daily global horizontal irradiance data were evaluated with 41 BSRN stations worldwide, 294 stations in Europe, and two satellite-derived products (NSRDB and SARAH) [...].We conclude that ERA5 and COSMO-REA6 have reduced the gap between reanalysis and satellite-based data, but further development is required in the prediction of clouds while the spatial grid of ERA5 (31km) remains inadequate for places with high variability of surface irradiance (coasts and mountains). Satellite-based data should be still used when available [...].

Wald L., 2007. "Solar radiation energy (fundamentals)". In Solar Energy Conversion and Photoenergy Systems, edited by Julian Blanco and Sixto Malato, in Encyclopedia of Life Support Systems (EOLSS), Developed under the Auspices of the UNESCO, Eolss Publishers, Oxford ,UK, [http://www.eolss.net]

Content: Temporal and spatial characteristics of Saudi Arabian dust storms, with focus on associated air parcel trajectories, are investigated using station and gridded weather observations and remotely-sensed aerosol optical depth (AOD)

Content: Presentation of the monthly maps of MODIS parameters (fiso, fvol and fgeo) used to generate albedo for each instant in the year, derived from holy maps of collected MODIS maps (holes due to clouds).

Content: Even if this paper has finally been rejected, I (Claire THOMAS, Transvalor) recommend you to have a look to this work. It consists of an extension of the previous paper (Blanc et al. 2014) in ten spectral bands.

Content: Presentation of the monthly maps of MODIS parameters (fiso, fvol and fgeo) used to generate albedo for each instant in the year, derived from holy maps of collected MODIS maps (holes due to clouds).

Content: In this publication, Cano et al. recommended to apply the Heliosat-2 method only for the slots when the sun is above 18° of elevation. We decided to slightly descrease this threshold to 12° in our implementation of Heliosat-2 (HelioClim-3).

Content: Table 3 p 2119 gives the uncertainty on the GHI, DHI and BHI components measured by the BSRN stations: +/-5 W/m² for the GHI and the DHI components, and +/-2 W/m² for the BHI. This is why a threshold of respectively 10 W/m² and 4 W/m² is applied on the measurements in the adopted quality check procedure.

Content: in addition to the description of CAMS McClear, this article provides a very restrictive algorithm to select clear sky instants. It consists of two successive filters. The first one is a constraint on the amount of diffuse irradiance with respect to the global irradiance since the direct irradiance is usually prominent in the case of clear sky. The second filter analyses the temporal variability of the global irradiance. If there is no cloud, the sky should be clear and steady for a long period.

Content: the Kato bands do not exactly fit the PAR spectral ranges and a spectral resampling is necessary. The authors have developed a resampling method which determine several 1-nm spectral bands whose atmospheric transmissivities are correlated to those of the Kato bands and then use these transmissivities in a linear interpolation process to compute the PAR irradiance. The technique has been numerically validated. The authors conclude that the technique estimates direct and global with very high accuracy.

Content: authors compared atmospheric transmissivities obtained by the Kato et al. approach against those obtained by spectrally resolved computations using two Radiative Transfer Models (RTMs) in each of the 32 Kato Bands. These calculations were performed for a set of 200 000 realistic atmospheres and clouds. These authors found that the Kato et al. approach offers very accurate estimates of irradiances in all 12 Kato bands covering PAR-range.

Content: On the PVPMC website, scripts are available to model temporal variability and provides a map over USA to support the use of this application. In order to calibrate models, wind speed and direction is needed. The matter of variability in the PV sector is more and more stringent in particular on islands with coupled PV system+ storage solutions.

Content: objective validation results ordered by Transvalor directly to Pierre Ineichen. Major result underlined by Pierre is the improvement of version 5 of HelioClim-3 (CAMS McClear clear sky model) compared to obsolete version 4. Please note that these results don't take into account version 3 of CAMS McClear available since Oct. 2017.

Content: the solar hourly global irradiation received at ground level estimated by the databases HelioClim- 3v4, HelioClim-3v5 and CAMS Radiation Service are compared to coincident measurements made in five stations in Oman (Sunainah, Adam Airport, Sur, Muscat Airport) and Abu Dhabi (Shams). 5 stations - poster . Please note that these results are obsolete since they doesn't take into account the bias correction and McClear v3 of Oct. 2017.

Content: If you need to handle the measurements of the Diffuse Horizontal component acquired by a pyranometer and a shadow-band, the values will likely be underestimated. This is due to the fact that the band is occulting a part of the sky and thus a part of diffuse that should be collected by the sensor. Here at MINES ParisTech/Transvalor, we decided to apply the Muneer-Zhang correction which sligthly increase the values for the diffuse component.